JP3774699B2 - Method and apparatus for transmitting information having a voice part and a data part - Google Patents

Description

[0001]
The present invention relates to a method and an apparatus for transmitting information having a voice part and a data part based on the Internet Protocol (IP) in a communication system according to the superordinate concept of claim 1.
[0002]
With the integration of computers into communication services, IP-based information transmission is increasingly incorporated into communication systems. While transmitting audio information for telephone services, information with audio content and data content is transmitted for a number of applications such as video conferencing services.
[0003]
Information is compressed before transmission to ensure an optimal transmission rate or transmission bandwidth. The audio part can be compressed with loss, but the algorithm used for it cannot be applied to the data part of the information. This is because it causes undesirable information loss.
[0004]
In addition, it is often useful to use different transmission protocols for each part transmission. Therefore, the information to be transmitted is divided into a voice part and a data part and transmitted separately from each other.
[0005]
FIG. 3 schematically shows an information transmission apparatus in a conventional communication system. Information on the transmission side 10 with respect to the reception side 40 is separately transmitted to the second interface unit 30 via the first interface unit 20 in accordance with the audio part and the data part. The separate transmission for each part is controlled by a control message (dashed arrow). It is symbolically shown that bidirectional data traffic is performed by arrows. This is because an acknowledgment is made for receipt of this type of control message.
[0006]
The conventional transmission operation in each interface unit 20 and 30 is shown in the left half and the right half of FIG. The first interface unit 20 receives information to be transmitted to the receiving side 40 from the transmitting side 10, and this information includes both a voice part and a data part. In the first step (division), information is divided into parts. Then, in the second step (encoding), the audio part and the data part are compressed and formatted according to the protocol used. The voice part and the data part are transmitted to two different ports of the second interface unit 30.
[0007]
In order to allow the second interface unit 30 to identify the relevance of each part, an appropriate control message is transmitted in the higher protocol layer. In the example shown here, H.264 is used to notify the second interface unit of two ports. A H.323 message is used. H. H.323 is a standard that defines components, procedures, and protocols for audio-visual communication over a packet-switched network.
[0008]
The second interface unit 30 receives the H.264 received in the first step (decoding). It interprets the H.323 message and maps each part accordingly. In the second step (synthesis), the original information is synthesized from each part and transferred to the receiving side 40.
[0009]
Since it is necessary to first establish a connection by a control message before transmission can be performed, time loss occurs due to transmission, response, and processing of the control message.
[0010]
SUMMARY OF THE INVENTION An object of the present invention is to provide a method and apparatus that avoids time loss due to control messages.
[0011]
According to the invention, this problem is solved by a method according to claim 1 or an apparatus according to claim 11. The dependent claims contain advantageous embodiments of the invention.
[0012]
According to the present invention, when information having an audio part and a data part is transmitted from the first interface unit to the second interface unit based on the Internet protocol (IP), the audio part and the data part are respectively used by using different ports. Information is transmitted separately. In this case, in the second interface unit, the related transmitted audio part and data part are associated with each other based on the fixedly determined port. Since the associated information is transmitted to the associated port, no additional control message is required.
[0013]
According to one advantageous embodiment of the method according to the invention, more than two ports are negotiated for each associated port. Thus, the interface unit can pick the appropriate combination from the ports needed for information.
[0014]
According to another advantageous embodiment of the method according to the invention, the data part is transmitted using a transmission control protocol (TCP), which guarantees a fixed order and error correction of the data packets. Particularly preferred is the transmission of the voice part by means of a user datagram (UDP), since a high transmission rate is guaranteed by UDP.
[0015]
According to an additional embodiment of the method according to the invention, the data part consists of a combination of several data types, which supports different data types and thus different applications.
[0016]
According to one advantageous embodiment of the method according to the invention, the information is divided into an audio part and a data part in the area of the first interface unit. This makes it possible to use this method without depending on the interface of various application cases.
[0017]
According to yet another advantageous embodiment of the method according to the invention, the audio part is compressed with loss before transmission, so that a faster transmission is achieved.
[0018]
According to the invention, a device in a communication system is provided with two interfaces having a plurality of ports, whereby any one of the methods recited in each claim is performed.
[0019]
The invention will now be described on the basis of advantageous embodiments with reference to the drawings.
[0020]
FIG. 1 shows a device according to the invention in a communication system.
[0021]
FIG. 2 shows the method according to the invention for the first and second interface units depicted in FIG.
[0022]
FIG. 3 is a diagram showing an apparatus in a conventional communication system.
[0023]
FIG. 4 is a diagram illustrating a conventional method for the first and second interface units depicted in FIG.
[0024]
FIG. 1 shows a device according to the invention, which comprises a transmitting side 10, a receiving side 40, a first interface unit 20 and a second interface unit 30. Information to be transmitted from the transmission side 10 to the reception side 40 is divided into a voice part and a data part and separately transmitted to the second interface unit 30 using two ports of the first interface unit 20. The second port for the data part is fixedly associated with the first port for the voice part.
[0025]
In the left half of FIG. 2, a schematic flow in the first interface unit 20 is described as an example. The received information to be transmitted is divided into an audio part and a data part in the first step (division). As a feature for the data part, for example, a sequence of dual tone multi-frequency selection schemes can be identified. In the second step (encoding), the audio part is compressed with loss, whereas the data part is compressed without loss using some algorithm. The data part is then transmitted to two different ports in the second interface unit 30 using TCP and the voice part using UDP. Selection of a port to be used for transmission is performed according to a list (definition) in which each port is individually or pair-wise or grouped and assigned to one connection.
[0026]
In the right half of FIG. 2, a sequence in the second interface unit 30 is depicted. The audio part and the data part of the information are received at different ports and are decompressed separately from each other in the first step (decoding), and then the parts are associated with each other according to the definition. In order to transfer the information to the receiving side 40, the audio part and the data part are again synthesized in the second step (synthesis) to form complete information.
[0027]
Since the connection between the sender 10 and the receiver 40 usually has an information stream that is at least broken down into individual packets in the Internet protocol, FIGS. 2 and 4 only show the principle of this scheme. The passage of time is not shown.
[0028]
Transmission control protocol (TCP) and user diagram protocol (UDP) are known as IP-based transmission protocols. In this case, data transmission is serviced by TCP. This is because TCP, which is a connection-type transmission service, guarantees complete transmission without error in a predetermined packet order. UDP, which is connectionless, provides a higher speed for transmission. This is because connection establishment and cancellation and confirmation response are omitted during communication. In both UDP and TCP, the transmission packet is associated with the source application or the target application through a port.
[0029]
The data part may be constituted by image data, may be another data type, or may be constituted by a combination of image data and another data type. Thus, for example, the data part can be significantly larger than the audio part. In such situations, or if the application imposes higher demands on the transmission speed of the data part, use, for example, three ports for the data part and one port for the voice part It is useful to do. It is necessary to include such a combination of ports in the definition before application.
[0030]
The transmitting side 10 and the receiving side 40 can be, for example, telephones with images or computers with microphones. Also, the interface units 20 and 30 can be gateways or exchanges in the communication system, for which the information stream appears mixed or unpredictable with the voice part or data part as information of one connection. there is a possibility. However, it is also possible for the information to be generated by dividing it into those parts already in the first interface unit. Further, if the terminal device has a plurality of interfaces, the interface unit may be regarded as a terminal device.
[Brief description of the drawings]
FIG. 1 shows a device according to the invention in a communication system.
2 shows a method according to the invention for the first and second interface unit depicted in FIG. 1;
FIG. 3 is a diagram showing an apparatus in a conventional communication system.
4 illustrates a conventional method for the first and second interface units depicted in FIG.

Claims (11)

In a method for transmitting information having a voice part and a data part related to each other between interface units of a communication system using a plurality of ports based on the Internet Protocol (IP),
Transmitting the information from the first interface unit to the second interface unit separately using different ports according to the audio part and the data part;
Associating, in the second interface unit, transmitted audio parts and data parts associated with each other in the information,
The association, and performing based on the definition to be assigned to one connection fixedly negotiated ports to audio part and a data part mutually related to each other,
A method for transmitting information having a voice part and a data part based on the Internet protocol. The method of claim 1, wherein more than two ports are negotiated as being associated with each other. The method according to claim 1 or 2, wherein the data part is transmitted as a transmission control protocol (TCP). The method according to any one of claims 1 to 3, wherein the voice part is transmitted as a user datagram protocol (UDP). The method according to claim 1, wherein the data part includes image data. The method according to claim 1, wherein the data part comprises a combination of a plurality of data types. 7. The method according to claim 1, wherein the information is divided into a voice part and a data part in the area of the first interface unit. The method according to claim 1, wherein the parts are synthesized in the area of the second interface unit. 9. A method according to any one of the preceding claims, wherein the audio part is compressed with loss before transmission. The method according to claim 1, wherein the data part is compressed before transmission. 11. An apparatus in a communication system, characterized in that two interface units with a plurality of ports are provided, the interface unit performing the method according to any one of claims 1 to 10.

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